CN201382827Y - Differential pressure heat meter - Google Patents

Abstract

The utility model discloses a differential pressure heat meter, wherein a transmission antenna is arranged on one side of a heat calculation instrument, and a temperature sensor connector is arranged on the other side thereof, a differential pressure sensor is arranged on the lower portion of the heat calculation instrument, and a throttling device is arranged on the lower portion of the differential pressure sensor, and is formed by the butt-joint of a left clamping strap and a right clamping strap whose centers are provided with through-holes which have the same caliber, a nozzle is arranged between the left clamping strap and the right clamping strap, and the caliber of the nozzle on the right clamping strap is small, the upper side walls of the left clamping strap and the right clamping strap are respectively provided with a left pressure pipe and a right pressure pipe, the high pressure end of the differential pressure sensor is connected in the left clamping strap from the left pressure pipe, and the low pressure end thereof is connected in the right clamping strap through the right pressure pipe. The differential pressure heat meter has compact structure, high metering precision and excellent reliability, and does not consider the settlement of foreign matters.

Description

The differential pressure type calorimeter

Technical field:

The utility model belongs to technical field of physical instruments, especially relates to a kind of differential pressure type calorimeter of heat supply heating control metering system.

Technical background:

For a long time, the northern area of China town dweller's winter heating is generally pressed the usable floor area of dwelling house rather than is pressed actual mode meterage with heat with heat, cause user's awareness of saving energy relatively poor, when indoor temperature is higher simultaneously, the heat release of just windowing, also cause the waste of resource, this metering method is to lack science.And some developed countries are at the eighties initial stage in the west, and the use of calorimeter is quite general, and the means of metering are also different, and heating power department is with foundation and the means of calorimeter as the valuation charge.Basic measures as building energy conservation, China nation-building department lists the heat metering charge in the developing goal of " building energy conservation the ninth five-year plan and planning in 2010 ", spell out in the target: " covil construction of central heating are installed hotlist and relevant conditioning equipment and by the work of table meterage; obtained effect by pilot in 1998; begin to promote; carried out in flakes in key cities in 2000, finished substantially in 2010 years.Realize that heat metering charge infrastructure is the heat energy table that can measure with the heat that enough precision are used reality." at calorimeter as means and the foundation of Thermal Corp to each beneficiary that heats (resident family) valuation charge, not only extensively accepted, and the energy-conservation 20-30% that reaches by the user.Concerning China, the heating metering charge is imperative.Therefore, it is imperative that research and development are used for the calorimeter of heating valuation.

Traditional calorimeter is combined by flowmeter, temperature sensor and counter, the rotary wind type magnetic that calorimeter generally adopts passes the mechanical type hot water gauge, its impeller metering mechanism is the rotation that changes impeller through the water yield of flowmeter into, relation according to N=KvQ connects impeller rotation N and water yield Q, the ratio of gear of gear counting mechanism has just been represented flow coefficient k v, and it is changeless, single.

In fact, it is relevant with manufacturing accuracy that rotary wind type magnetic passes mechanical type hot water gauge flow coefficient k v, and change with flow (flow velocity), variation of temperature, and particularly in the low discharge district that demarcates below the flow, its variation is more remarkable.Again because hot water gauge factory does not have hot water flow standard test device, factory inspection is carried out on the cold water device, almost do not consider the influence of temperature convection coefficient of discharge Kv, because the situation ubiquity of China's heating system water quality inferiority, reduced the reliability of calorimeter, and be subject to static magnetic field and disturb, so it can not satisfy the measuring requirement of calorimeter to hot water flow.

Moreover, the present calorimeter that uses, its water inlet is connected by a cavity with water delivering orifice, current circulate from bottom to top by impeller, housing is easy to generate sediment in the chamber, and impurity is too many, stops up cavity easily, and impeller shaft is not wear-resisting, it is more serious to wear and tear, and the mission life of this structure impeller is short, consumes big, the cost height, and measuring accuracy is poor.

Therefore the inferior position of traditional heat metering method: tradition adopts water meter measurement of discharge integrating heat enthalpy value, and water meter is movable parts, easily get rusty or stopped up the card table by impurity, and degree of accuracy and accuracy is not high, can not satisfy the accurate measurement of heat; The thermometric degree tables look-up the integrating heat enthalpy value, and temperature survey need be tabled look-up, and manually integrating is loaded down with trivial details, expends a large amount of time and manpower.

The utility model content:

The purpose of this utility model provides a kind of compact conformation, does not worry contamination precipitation, measuring accuracy height, the differential pressure type calorimeter of good reliability.

For achieving the above object, the technical solution of the utility model is: design a kind of differential pressure type calorimeter, be provided with transmit antenna in heat Calculation instrument one side, opposite side is provided with the temperature sensor joint, its main points are: be provided with differential pressure pick-up below described heat Calculation instrument, this differential pressure pick-up is connected with the heat Calculation instrument, make it signal can be transferred to the heat Calculation instrument, below this differential pressure pick-up, be provided with restriction device, described restriction device is equipped with the left side of the through hole of bore unanimity by central authorities, right clamping plate butt joint forms, on this left side, be provided with nozzle between the right clamping plate, and the bore that this nozzle is positioned at right clamping plate part is little, on a described left side, be respectively equipped with a left side on the right clamping plate upper portion side wall, right pressure guiding pipe, the high-pressure side of described differential pressure pick-up inserts left clamping plate from left pressure guiding pipe, low pressure end inserts right clamping plate from right pressure guiding pipe, described restriction device is installed in the water inlet pipe or rising pipe of heating system, under the effect of restriction device, owing to be full of the fluid of pipeline, during restriction device in it flows through pipeline, flow velocity will form local contraction at the restriction device place, thereby the flow velocity increase, static pressure reduces, so just produced pressure reduction before and after throttling element.Fluid flow is bigger, and the pressure reduction of generation is bigger, can weigh the size of flow like this according to pressure reduction, and so, differential pressure pick-up just can be measured the flow of restriction device inner fluid; On the water inlet pipe of heating system and rising pipe, temperature sensor is housed respectively,, signal is imported the heat Calculation instrument the signal cut-in temperature sensor connector of temperature sensor.The temperature difference that fluid flow that the heat Calculation instrument is measured differential pressure pick-up with flow continuity equation (law of conservation of mass) and Bernoulli equation (law of conservation of energy) and temperature sensor are measured is calculated, and just can obtain the heat that is consumed.

Be provided with the protection housing in described heat Calculation instrument lower end, described differential pressure pick-up is positioned at described protection housing, so just can effectively protect this accurate device of differential pressure pick-up, moistureproof or prevent foreign matter from entering and cause measurement than mistake.

Described containment vessel body and function support is fixed on the restriction device; the high-pressure side of described differential pressure pick-up and low pressure end pass described support and insert left clamping plate and insert right clamping plate from right pressure guiding pipe from left pressure guiding pipe respectively; be provided with support can be preferably will the protection housing and restriction device connect as one, be easy to carry and move.

Described left clamping plate are connected with fastening bolt with right clamping plate butt joint back, so can either well restriction device be fixed, and are convenient to dismounting again.

Effect of the present utility model:

1, because direct gaging pressure/differential pressure, no movable member, so impurity can directly pass through in the hot water need not worried to cause that by impurity card maybe can't be worked etc.;

2, owing to adopt precision casting, non-corrosive is used at the scene, and protective is better;

3, adopt the high-precision wide amount can measure wide range of traffic and change (100: 1), so high-precision flow is measured high precision heat Calculation, flow accuracy≤1% than differential pressure pick-up;

4, adopt the nozzle restriction device, pressure decreases littler;

5, data wireless transmission technology realizes remote meter reading.

Principle of the present utility model is: the transmission of heat is generally determined by the factors such as quality, specific heat capacity and temperature variation of heat transport fluid.Concerning calorimeter, the enthalpy of import and export is also proportional with the time.Domestic calorimeter generally adopts enthalpy potential method to calculate heat.The heat transfer formula of enthalpy potential method is:

$Q={\&Integral;}_{t0}^{\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="Y2009201271370011H1.png"\; state="\{\{state\}\}">t</figure-callout>}1}\mathrm{G\&Delta;h}\&CenterDot;\mathrm{dt}$

In the formula: Q is release heat kj or kwh; G is mass rate kg/s; Δ h is for importing and exporting enthalpy difference kj/kg; T is time s;

Parsing by to flow continuity equation (law of conservation of mass) and Bernoulli equation (law of conservation of energy) obtains formula Q=G (H according to the heat transfer formula _In-H _Out)=∫ c * G _t* (T ₁-T ₂Therefore) * dt can measure the heat that calculates the user then and consumed to flow, temperature, time.

1, utilizes temperature sensor measuring and calculating temperature

Temperature-sensing element adopts platinum resistance pt1000, and in 0～850 ℃ temperature range, the resistance of platinum resistance and the pass of temperature are:

R(t)＝R(0℃)(1+At+Bt ²)

In the formula: A=3.9083 * 10 ^-3℃ ^-1B=-5.775 * 10 ^-7-℃ ^-2

Obviously the resistance by platinum resistance is difficult to obtain temperature value, can use schedule method and linear skewer value method to carry out the scale transformation of temperature.Resistance value compares in resistance value that is about to record and the form, stops comparison when Rn＜R＜Rn+1.The integral part that the pairing temperature value tn of Rn this moment is a measured temperature, and the fraction part of temperature:

Δt＝t-t _n＝(R-R _n)/(R _n+1-R _n) 0℃＜Δt＜1℃

2, utilize differential pressure pick-up measuring and calculating flow

Adopt high precision band overvoltage protection capacitance differential pressure transducer that the unit mass flow G of hot water is carried out accurate measurement; Utilize Bernoulli equation and continuity equation to derive the relation equation of static pressure loss Δ p and flow G

$G=A_2{u}_2{\mathrm{\&rho;}}_2=\frac{A_2}{\sqrt{1-{\left(\frac{A_2}{A_1}\right)}^2}}\sqrt{2{\mathrm{\&rho;}}_2\mathrm{\&Delta;p}};$

Wherein: ρ ²=-2E ^-12T ₂ ⁶+ 8E ^-10T ₂ ⁵-3E ^-7T ₂ ⁴+ 5E ^-5T ₂ ³-0.0077T ₂ ²+ 0.0519T ²+ 999.9

3, measure the time

4, bring flow, temperature, the time of calculating into formula Q=G (H _In-H _Out)=∫ c * G _t* (T ₁-T ₂) * dt calculates, and can obtain the heat that the user consumes.

Description of drawings

Fig. 1 is a structural representation of the present utility model;

Fig. 2 is user mode figure of the present utility model.

Meaning of each numbering is in the above-mentioned accompanying drawing: 1. heat Calculation instrument, 2. transmit antenna, 3. temperature sensor joint; 4. differential pressure pick-up, 5. left clamping plate, 6. right clamping plate; 7. nozzle, 8. left pressure guiding pipe, 9. right pressure guiding pipe; 10. protection housing, 11. supports, 12. fastening bolts; 13. water inlet pipe; 14. rising pipe, 15. heat-exchange systems, 16. temperature sensors.

Embodiment:

Below in conjunction with accompanying drawing the utility model is further described.

See also Fig. 1: shown in the differential pressure type calorimeter; it is by heat Calculation instrument 1; transmit antenna 2; compositions such as temperature sensor joint 3 and differential pressure pick-up 4; be provided with transmit antenna 2 in heat Calculation instrument 1 one sides; opposite side is provided with temperature sensor joint 3; be provided with protection housing 10 in described heat Calculation instrument 1 lower end; described differential pressure pick-up 4 is positioned at described protection housing 10; this differential pressure pick-up 4 is connected with heat Calculation instrument 1; below described differential pressure pick-up 4, be provided with restriction device; described restriction device is equipped with the left side of the through hole of bore unanimity by central authorities; right clamping plate 5; 6 butt joints form; and connect with fastening bolt 12; on this left side; right clamping plate 5; be provided with nozzle 7 between 6; and the bore that this nozzle 7 is positioned at right clamping plate 6 parts is little; on a described left side; right clamping plate 5; be respectively equipped with a left side on 6 upper portion side wall; right pressure guiding pipe 8; 9; the high-pressure side of described differential pressure pick-up 4 inserts left clamping plate 5 from left pressure guiding pipe 8, and low pressure end inserts right clamping plate 6 from right pressure guiding pipe 9.

It can also be seen that in Fig. 1: described protection housing 10 usefulness supports 11 are fixed on the restriction device, and the high-pressure side of described differential pressure pick-up 4 and low pressure end pass described support 11 and insert left clamping plate 5 and insert right clamping plate 6 from right pressure guiding pipe 9 from left pressure guiding pipe 8 respectively.

See also Fig. 2: shown in differential pressure type calorimeter user mode figure, heat-exchange system 15 outsides are connected to water inlet pipe 13 and rising pipe 14, the restriction device of described differential pressure type calorimeter lower end is installed on the water inlet pipe 13, two signal ends with temperature sensor joint 3 are connected on respectively on the temperature sensor 16 of water inlet pipe 13 and rising pipe 14 again, so, when whole device work, just can measure, directly just can read from the heat Calculation instrument to the heat in the heat-exchange system.

Claims (4)

1, a kind of differential pressure type calorimeter, be provided with transmit antenna (2) in heat Calculation instrument (1) one side, opposite side is provided with temperature sensor joint (3), it is characterized in that: be provided with differential pressure pick-up (4) in described heat Calculation instrument (1) below, be provided with restriction device in this differential pressure pick-up (4) below, described restriction device is equipped with the left side of the through hole of bore unanimity by central authorities, right clamping plate (5,6) butt joint forms, on this left side, right clamping plate (5,6) be provided with nozzle (7) between, and the bore that this nozzle (7) is positioned at right clamping plate (6) part is little, on a described left side, right clamping plate (5,6) be respectively equipped with a left side on the upper portion side wall, right pressure guiding pipe (8,9), the high-pressure side of described differential pressure pick-up (4) inserts left clamping plate (5) from left pressure guiding pipe (8), and low pressure end inserts right clamping plate (6) from right pressure guiding pipe (9).

2, differential pressure type calorimeter according to claim 1 is characterized in that: be provided with protection housing (10) in described heat Calculation instrument (1) lower end, described differential pressure pick-up (4) is positioned at described protection housing (10).

3, differential pressure type calorimeter according to claim 1; it is characterized in that: described protection housing (10) is fixed on the restriction device with support (11), and the high-pressure side of described differential pressure pick-up (4) and low pressure end pass described support (11) and insert left clamping plate (5) and insert right clamping plate (6) from right pressure guiding pipe (9) from left pressure guiding pipe (8) respectively.

4, differential pressure type calorimeter according to claim 1 is characterized in that: described left clamping plate (5) are connected with fastening bolt (12) with right clamping plate (6) butt joint back.

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